1
|
López-Carbonero JI, García-Toledo I, Fernández-Hernández L, Bascuñana P, Gil-Moreno MJ, Matías-Guiu JA, Corrochano S. In vivo diagnosis of TDP-43 proteinopathies: in search of biomarkers of clinical use. Transl Neurodegener 2024; 13:29. [PMID: 38831349 PMCID: PMC11149336 DOI: 10.1186/s40035-024-00419-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/06/2024] [Indexed: 06/05/2024] Open
Abstract
TDP-43 proteinopathies are a heterogeneous group of neurodegenerative disorders that share the presence of aberrant, misfolded and mislocalized deposits of the protein TDP-43, as in the case of amyotrophic lateral sclerosis and some, but not all, pathological variants of frontotemporal dementia. In recent years, many other diseases have been reported to have primary or secondary TDP-43 proteinopathy, such as Alzheimer's disease, Huntington's disease or the recently described limbic-predominant age-related TDP-43 encephalopathy, highlighting the need for new and accurate methods for the early detection of TDP-43 proteinopathy to help on the stratification of patients with overlapping clinical diagnosis. Currently, TDP-43 proteinopathy remains a post-mortem pathologic diagnosis. Although the main aim is to determine the pathologic TDP-43 proteinopathy in the central nervous system (CNS), the ubiquitous expression of TDP-43 in biofluids and cells outside the CNS facilitates the use of other accessible target tissues that might reflect the potential TDP-43 alterations in the brain. In this review, we describe the main developments in the early detection of TDP-43 proteinopathies, and their potential implications on diagnosis and future treatments.
Collapse
Affiliation(s)
- Juan I López-Carbonero
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - Irene García-Toledo
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - Laura Fernández-Hernández
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - Pablo Bascuñana
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - María J Gil-Moreno
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - Jordi A Matías-Guiu
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain
| | - Silvia Corrochano
- Neurological Disorders Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040, Madrid, Spain.
| |
Collapse
|
2
|
Rebak AS, Hendriks IA, Elsborg JD, Buch-Larsen SC, Nielsen CH, Terslev L, Kirsch R, Damgaard D, Doncheva NT, Lennartsson C, Rykær M, Jensen LJ, Christophorou MA, Nielsen ML. A quantitative and site-specific atlas of the citrullinome reveals widespread existence of citrullination and insights into PADI4 substrates. Nat Struct Mol Biol 2024; 31:977-995. [PMID: 38321148 PMCID: PMC11189309 DOI: 10.1038/s41594-024-01214-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 01/04/2024] [Indexed: 02/08/2024]
Abstract
Despite the importance of citrullination in physiology and disease, global identification of citrullinated proteins, and the precise targeted sites, has remained challenging. Here we employed quantitative-mass-spectrometry-based proteomics to generate a comprehensive atlas of citrullination sites within the HL60 leukemia cell line following differentiation into neutrophil-like cells. We identified 14,056 citrullination sites within 4,008 proteins and quantified their regulation upon inhibition of the citrullinating enzyme PADI4. With this resource, we provide quantitative and site-specific information on thousands of PADI4 substrates, including signature histone marks and transcriptional regulators. Additionally, using peptide microarrays, we demonstrate the potential clinical relevance of certain identified sites, through distinct reactivities of antibodies contained in synovial fluid from anti-CCP-positive and anti-CCP-negative people with rheumatoid arthritis. Collectively, we describe the human citrullinome at a systems-wide level, provide a resource for understanding citrullination at the mechanistic level and link the identified targeted sites to rheumatoid arthritis.
Collapse
Affiliation(s)
- Alexandra S Rebak
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ivo A Hendriks
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas D Elsborg
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara C Buch-Larsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claus H Nielsen
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Lene Terslev
- Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Rebecca Kirsch
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dres Damgaard
- Institute for Inflammation Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Nadezhda T Doncheva
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Caroline Lennartsson
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Martin Rykær
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars J Jensen
- Disease Systems Biology Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Michael L Nielsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
3
|
Sun X, Wu L, Du L, Xu W, Han M. Targeting the organelle for radiosensitization in cancer radiotherapy. Asian J Pharm Sci 2024; 19:100903. [PMID: 38590796 PMCID: PMC10999375 DOI: 10.1016/j.ajps.2024.100903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/29/2023] [Accepted: 01/16/2024] [Indexed: 04/10/2024] Open
Abstract
Radiotherapy is a well-established cytotoxic therapy for local solid cancers, utilizing high-energy ionizing radiation to destroy cancer cells. However, this method has several limitations, including low radiation energy deposition, severe damage to surrounding normal cells, and high tumor resistance to radiation. Among various radiotherapy methods, boron neutron capture therapy (BNCT) has emerged as a principal approach to improve the therapeutic ratio of malignancies and reduce lethality to surrounding normal tissue, but it remains deficient in terms of insufficient boron accumulation as well as short retention time, which limits the curative effect. Recently, a series of radiosensitizers that can selectively accumulate in specific organelles of cancer cells have been developed to precisely target radiotherapy, thereby reducing side effects of normal tissue damage, overcoming radioresistance, and improving radiosensitivity. In this review, we mainly focus on the field of nanomedicine-based cancer radiotherapy and discuss the organelle-targeted radiosensitizers, specifically including nucleus, mitochondria, endoplasmic reticulum and lysosomes. Furthermore, the organelle-targeted boron carriers used in BNCT are particularly presented. Through demonstrating recent developments in organelle-targeted radiosensitization, we hope to provide insight into the design of organelle-targeted radiosensitizers for clinical cancer treatment.
Collapse
Affiliation(s)
- Xiaoyan Sun
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
- National Key Laboratory of Advanced Drug Delivery and Release Systems, Zhejiang University, Hangzhou 310058, China
| | - Linjie Wu
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
- National Key Laboratory of Advanced Drug Delivery and Release Systems, Zhejiang University, Hangzhou 310058, China
| | - Lina Du
- Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing 100850, China
| | - Wenhong Xu
- Department of Radiation Oncology, Key Laboratory of Cancer Prevention and Intervention, The Second Afliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Min Han
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
- Department of Radiation Oncology, Key Laboratory of Cancer Prevention and Intervention, The Second Afliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310058, China
- Hangzhou Institute of Innovative Medicine, Zhejiang University, Hangzhou 310058, China
- Jinhua Institute of Zhejiang University, Jinhua 321299, China
- National Key Laboratory of Advanced Drug Delivery and Release Systems, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
4
|
Mitra J, Dharmalingam P, Kodavati MM, Guerrero EN, Rao KS, Garruto R, Hegde ML. Endogenous TDP-43 mislocalization in a novel knock-in mouse model reveals DNA repair impairment, inflammation, and neuronal senescence. RESEARCH SQUARE 2024:rs.3.rs-3879966. [PMID: 38343852 PMCID: PMC10854316 DOI: 10.21203/rs.3.rs-3879966/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/19/2024]
Abstract
TDP-43 mislocalization and aggregation are key pathological features of motor neuron diseases (MND) including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, transgenic hTDP-43 WT or ∆NLS-overexpression animal models mainly capture late-stages TDP-43 proteinopathy, and do not provide a complete understanding of early motor neuron-specific pathology during pre-symptomatic phases. We have now addressed this shortcoming by generating a new endogenous knock-in (KI) mouse model using a combination of CRISPR/Cas9 and FLEX Cre-switch strategy for the conditional expression of a mislocalized Tdp-43∆NLS variant of mouse Tdp-43. This variant is either expressed conditionally in whole mice or specifically in the motor neurons. The mice exhibit loss of nuclear Tdp-43 concomitant with its cytosolic accumulation and aggregation in targeted cells, leading to increased DNA double-strand breaks (DSBs), signs of inflammation and DNA damage-associated cellular senescence. Notably, unlike WT Tdp43 which functionally interacts with Xrcc4 and DNA Ligase 4, the key DSB repair proteins in the non-homologous end-joining (NHEJ) pathway, the Tdp-43∆NLS mutant sequesters them into cytosolic aggregates, exacerbating neuronal damage in mice brain. The mutant mice also exhibit myogenic degeneration in limb muscles and distinct motor deficits, consistent with the characteristics of MND. Our findings reveal progressive degenerative mechanisms in motor neurons expressing endogenous Tdp-43∆NLS mutant, independent of TDP-43 overexpression or other confounding etiological factors. Thus, this unique Tdp-43 KI mouse model, which displays key molecular and phenotypic features of Tdp-43 proteinopathy, offers a significant opportunity to further characterize the early-stage progression of MND and also opens avenues for developing DNA repair-targeted approaches for treating TDP-43 pathology-linked neurodegenerative diseases.
Collapse
|
5
|
Dao HM, AboulFotouh K, Hussain AF, Marras AE, Johnston KP, Cui Z, Williams RO. Characterization of mRNA Lipid Nanoparticles by Electron Density Mapping Reconstruction: X-ray Scattering with Density from Solution Scattering (DENSS) Algorithm. Pharm Res 2024; 41:501-512. [PMID: 38326530 DOI: 10.1007/s11095-024-03671-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 01/28/2024] [Indexed: 02/09/2024]
Abstract
PURPOSE This study aimed to test the feasibility of using Small Angle X-ray Scattering (SAXS) coupled with Density from Solution Scattering (DENSS) algorithm to characterize the internal architecture of messenger RNA-containing lipid nanoparticles (mRNA-LNPs). METHODS The DENSS algorithm was employed to construct a three-dimensional model of average individual mRNA-LNP. The reconstructed models were cross validated with cryogenic transmission electron microscopy (cryo-TEM), and dynamic light scattering (DLS) to assess size, morphology, and internal structure. RESULTS Cryo-TEM and DLS complemented SAXS, revealed a core-shell mRNA-LNP structure with electron-rich mRNA-rich region at the core, surrounded by lipids. The reconstructed model, utilizing the DENSS algorithm, effectively distinguishes mRNA and lipids via electron density mapping. Notably, DENSS accurately models the morphology of the mRNA-LNPs as an ellipsoidal shape with a "bleb" architecture or a two-compartment structure with contrasting electron densities, corresponding to mRNA-filled and empty lipid compartments, respectively. Finally, subtle changes in the LNP structure after three freeze-thaw cycles were detected by SAXS, demonstrating an increase in radius of gyration (Rg) associated with mRNA leakage. CONCLUSION Analyzing SAXS profiles based on DENSS algorithm to yield a reconstructed electron density based three-dimensional model can be a useful physicochemical characterization method in the toolbox to study mRNA-LNPs and facilitate their development.
Collapse
Affiliation(s)
- Huy M Dao
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Khaled AboulFotouh
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Aasim Faheem Hussain
- Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Alexander E Marras
- Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, USA
- Materials Science and Engineering Graduate Program, Texas Materials Institute, The University of Texas at Austin, Austin, TX, USA
- Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Keith P Johnston
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Zhengrong Cui
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA.
| | - Robert O Williams
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA.
| |
Collapse
|
6
|
Mohanty P, Rizuan A, Kim YC, Fawzi NL, Mittal J. A complex network of interdomain interactions underlies the conformational ensemble of monomeric TDP-43 and modulates its phase behavior. Protein Sci 2024; 33:e4891. [PMID: 38160320 PMCID: PMC10804676 DOI: 10.1002/pro.4891] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/07/2023] [Accepted: 12/28/2023] [Indexed: 01/03/2024]
Abstract
TAR DNA-binding protein 43 (TDP-43) is a multidomain protein involved in the regulation of RNA metabolism, and its aggregates have been observed in neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Numerous studies indicate TDP-43 can undergo liquid-liquid phase separation (LLPS) in vitro and is a component of biological condensates. Homo-oligomerization via the folded N-terminal domain (aa:1-77) and the conserved helical region (aa:319-341) of the disordered, C-terminal domain is found to be an important driver of TDP-43 phase separation. However, a comprehensive molecular view of TDP-43 phase separation, particularly regarding the nature of heterodomain interactions, is lacking due to the challenges associated with its stability and purification. Here, we utilize all-atom and coarse-grained (CG) molecular dynamics (MD) simulations to uncover the network of interdomain interactions implicated in TDP-43 phase separation. All-atom simulations uncovered the presence of transient, interdomain interactions involving flexible linkers, RNA-recognition motif (RRM) domains and a charged segment of disordered C-terminal domain (CTD). CG simulations indicate these inter-domain interactions which affect the conformational landscape of TDP-43 in the dilute phase are also prevalent in the condensed phase. Finally, sequence and surface charge distribution analysis coupled with all-atom simulations (at high salt) confirmed that the transient interdomain contacts are predominantly electrostatic in nature. Overall, our findings from multiscale simulations lead to a greater appreciation of the complex interaction network underlying the structural landscape and phase separation of TDP-43.
Collapse
Affiliation(s)
- Priyesh Mohanty
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTexasUSA
| | - Azamat Rizuan
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTexasUSA
| | - Young C. Kim
- Naval Research LaboratoryCenter for Materials Physics and TechnologyWashingtonDistrict of ColumbiaUSA
| | - Nicolas L. Fawzi
- Department of Molecular Biology, Cell Biology and BiochemistryProvidenceRhode IslandUSA
| | - Jeetain Mittal
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTexasUSA
- Department of ChemistryTexas A&M UniversityCollege StationTexasUSA
- Interdisciplinary Graduate Program in Genetics and GenomicsTexas A&M UniversityCollege StationTexasUSA
| |
Collapse
|
7
|
Khalil B, Linsenmeier M, Smith CL, Shorter J, Rossoll W. Nuclear-import receptors as gatekeepers of pathological phase transitions in ALS/FTD. Mol Neurodegener 2024; 19:8. [PMID: 38254150 PMCID: PMC10804745 DOI: 10.1186/s13024-023-00698-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 12/13/2023] [Indexed: 01/24/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative disorders on a disease spectrum that are characterized by the cytoplasmic mislocalization and aberrant phase transitions of prion-like RNA-binding proteins (RBPs). The common accumulation of TAR DNA-binding protein-43 (TDP-43), fused in sarcoma (FUS), and other nuclear RBPs in detergent-insoluble aggregates in the cytoplasm of degenerating neurons in ALS/FTD is connected to nuclear pore dysfunction and other defects in the nucleocytoplasmic transport machinery. Recent advances suggest that beyond their canonical role in the nuclear import of protein cargoes, nuclear-import receptors (NIRs) can prevent and reverse aberrant phase transitions of TDP-43, FUS, and related prion-like RBPs and restore their nuclear localization and function. Here, we showcase the NIR family and how they recognize cargo, drive nuclear import, and chaperone prion-like RBPs linked to ALS/FTD. We also discuss the promise of enhancing NIR levels and developing potentiated NIR variants as therapeutic strategies for ALS/FTD and related neurodegenerative proteinopathies.
Collapse
Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - Miriam Linsenmeier
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A..
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A..
| |
Collapse
|
8
|
Yang R, Ko YH, Li F, Lokareddy RK, Hou CFD, Kim C, Klein S, Antolínez S, Marín JF, Pérez-Segura C, Jarrold MF, Zlotnick A, Hadden-Perilla JA, Cingolani G. Structural basis for nuclear import of hepatitis B virus (HBV) nucleocapsid core. SCIENCE ADVANCES 2024; 10:eadi7606. [PMID: 38198557 PMCID: PMC10780889 DOI: 10.1126/sciadv.adi7606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024]
Abstract
Nuclear import of the hepatitis B virus (HBV) nucleocapsid is essential for replication that occurs in the nucleus. The ~360-angstrom HBV capsid translocates to the nuclear pore complex (NPC) as an intact particle, hijacking human importins in a reaction stimulated by host kinases. This paper describes the mechanisms of HBV capsid recognition by importins. We found that importin α1 binds a nuclear localization signal (NLS) at the far end of the HBV coat protein Cp183 carboxyl-terminal domain (CTD). This NLS is exposed to the capsid surface through a pore at the icosahedral quasi-sixfold vertex. Phosphorylation at serine-155, serine-162, and serine-170 promotes CTD compaction but does not affect the affinity for importin α1. The binding of 30 importin α1/β1 augments HBV capsid diameter to ~620 angstroms, close to the maximum size trafficable through the NPC. We propose that phosphorylation favors CTD externalization and prompts its compaction at the capsid surface, exposing the NLS to importins.
Collapse
Affiliation(s)
- Ruoyu Yang
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Ying-Hui Ko
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL 35294, USA
| | - Fenglin Li
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Ravi K. Lokareddy
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL 35294, USA
| | - Chun-Feng David Hou
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Christine Kim
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, IN 47405, USA
| | - Shelby Klein
- Department of Chemistry, Indiana University, Bloomington, Indiana, IN 47405, USA
| | - Santiago Antolínez
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Juan F. Marín
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Carolina Pérez-Segura
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Martin F. Jarrold
- Department of Chemistry, Indiana University, Bloomington, Indiana, IN 47405, USA
| | - Adam Zlotnick
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, IN 47405, USA
| | | | - Gino Cingolani
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL 35294, USA
| |
Collapse
|
9
|
Cross EM, Marin O, Ariawan D, Aragão D, Cozza G, Di Iorio E, Forwood JK, Alvisi G. Structural determinants of phosphorylation-dependent nuclear transport of HCMV DNA polymerase processivity factor UL44. FEBS Lett 2024; 598:199-209. [PMID: 38158756 DOI: 10.1002/1873-3468.14797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 01/03/2024]
Abstract
Human cytomegalovirus DNA polymerase processivity factor UL44 is transported into the nucleus by importin (IMP) α/β through a classical nuclear localization signal (NLS), and this region is susceptible to cdc2-mediated phosphorylation at position T427. Whilst phosphorylation within and close to the UL44 NLS regulates nuclear transport, the details remain elusive, due to the paucity of structural information regarding the role of negatively charged cargo phosphate groups. We addressed this issue by studying the effect of UL44 T427 phosphorylation on interaction with several IMPα isoforms by biochemical and structural approaches. Phosphorylation decreased UL44/IMPα affinity 10-fold, and a comparative structural analysis of UL44 NLS phosphorylated and non-phosphorylated peptides complexed with mouse IMPα2 revealed the structural rearrangements responsible for phosphorylation-dependent inhibition of UL44 nuclear import.
Collapse
Affiliation(s)
- Emily M Cross
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, Australia
- Diamond Light Source, Didcot, UK
| | - Oriano Marin
- Department of Biomedical Sciences, University of Padova, Italy
| | - Daryl Ariawan
- Dementia Research Centre, Macquarie University, Sydney, Australia
| | | | - Giorgio Cozza
- Department of Molecular Medicine, University of Padua, Italy
| | - Enzo Di Iorio
- Department of Molecular Medicine, University of Padua, Italy
| | - Jade K Forwood
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, Australia
| | | |
Collapse
|
10
|
García Morato J, Gloeckner CJ, Kahle PJ. Proteomics elucidating physiological and pathological functions of TDP-43. Proteomics 2023; 23:e2200410. [PMID: 37671599 DOI: 10.1002/pmic.202200410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/02/2023] [Accepted: 08/10/2023] [Indexed: 09/07/2023]
Abstract
Trans-activation response DNA binding protein of 43 kDa (TDP-43) regulates a great variety of cellular processes in the nucleus and cytosol. In addition, a defined subset of neurodegenerative diseases is characterized by nuclear depletion of TDP-43 as well as cytosolic mislocalization and aggregation. To perform its diverse functions TDP-43 can associate with different ribonucleoprotein complexes. Combined with transcriptomics, MS interactome studies have unveiled associations between TDP-43 and the spliceosome machinery, polysomes and RNA granules. Moreover, the highly dynamic, low-valency interactions regulated by its low-complexity domain calls for innovative proximity labeling methodologies. In addition to protein partners, the analysis of post-translational modifications showed that they may play a role in the nucleocytoplasmic shuttling, RNA binding, liquid-liquid phase separation and protein aggregation of TDP-43. Here we review the various TDP-43 ribonucleoprotein complexes characterized so far, how they contribute to the diverse functions of TDP-43, and roles of post-translational modifications. Further understanding of the fluid dynamic properties of TDP-43 in ribonucleoprotein complexes, RNA granules, and self-assemblies will advance the understanding of RNA processing in cells and perhaps help to develop novel therapeutic approaches for TDPopathies.
Collapse
Affiliation(s)
- Jorge García Morato
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Christian Johannes Gloeckner
- Research Group Functional Neuroproteomics, German Center of Neurodegenerative Diseases, Tübingen, Germany
- Core Facility for Medical Bioanalytics, Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Philipp J Kahle
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, German Center of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Biochemistry, University of Tübingen, Tübingen, Germany
| |
Collapse
|
11
|
Yang Y, Guo L, Chen L, Gong B, Jia D, Sun Q. Nuclear transport proteins: structure, function, and disease relevance. Signal Transduct Target Ther 2023; 8:425. [PMID: 37945593 PMCID: PMC10636164 DOI: 10.1038/s41392-023-01649-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 11/12/2023] Open
Abstract
Proper subcellular localization is crucial for the functioning of biomacromolecules, including proteins and RNAs. Nuclear transport is a fundamental cellular process that regulates the localization of many macromolecules within the nuclear or cytoplasmic compartments. In humans, approximately 60 proteins are involved in nuclear transport, including nucleoporins that form membrane-embedded nuclear pore complexes, karyopherins that transport cargoes through these complexes, and Ran system proteins that ensure directed and rapid transport. Many of these nuclear transport proteins play additional and essential roles in mitosis, biomolecular condensation, and gene transcription. Dysregulation of nuclear transport is linked to major human diseases such as cancer, neurodegenerative diseases, and viral infections. Selinexor (KPT-330), an inhibitor targeting the nuclear export factor XPO1 (also known as CRM1), was approved in 2019 to treat two types of blood cancers, and dozens of clinical trials of are ongoing. This review summarizes approximately three decades of research data in this field but focuses on the structure and function of individual nuclear transport proteins from recent studies, providing a cutting-edge and holistic view on the role of nuclear transport proteins in health and disease. In-depth knowledge of this rapidly evolving field has the potential to bring new insights into fundamental biology, pathogenic mechanisms, and therapeutic approaches.
Collapse
Affiliation(s)
- Yang Yang
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lu Guo
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lin Chen
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Bo Gong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Department of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Pediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China.
| | - Qingxiang Sun
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Centre, West China Hospital, Sichuan University, and Collaborative Innovation Centre of Biotherapy, Chengdu, China.
| |
Collapse
|
12
|
Necarsulmer JC, Simon JM, Evangelista BA, Chen Y, Tian X, Nafees S, Marquez AB, Jiang H, Wang P, Ajit D, Nikolova VD, Harper KM, Ezzell JA, Lin FC, Beltran AS, Moy SS, Cohen TJ. RNA-binding deficient TDP-43 drives cognitive decline in a mouse model of TDP-43 proteinopathy. eLife 2023; 12:RP85921. [PMID: 37819053 PMCID: PMC10567115 DOI: 10.7554/elife.85921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Abstract
TDP-43 proteinopathies including frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) are neurodegenerative disorders characterized by aggregation and mislocalization of the nucleic acid-binding protein TDP-43 and subsequent neuronal dysfunction. Here, we developed endogenous models of sporadic TDP-43 proteinopathy based on the principle that disease-associated TDP-43 acetylation at lysine 145 (K145) alters TDP-43 conformation, impairs RNA-binding capacity, and induces downstream mis-regulation of target genes. Expression of acetylation-mimic TDP-43K145Q resulted in stress-induced nuclear TDP-43 foci and loss of TDP-43 function in primary mouse and human-induced pluripotent stem cell (hiPSC)-derived cortical neurons. Mice harboring the TDP-43K145Q mutation recapitulated key hallmarks of FTLD, including progressive TDP-43 phosphorylation and insolubility, TDP-43 mis-localization, transcriptomic and splicing alterations, and cognitive dysfunction. Our study supports a model in which TDP-43 acetylation drives neuronal dysfunction and cognitive decline through aberrant splicing and transcription of critical genes that regulate synaptic plasticity and stress response signaling. The neurodegenerative cascade initiated by TDP-43 acetylation recapitulates many aspects of human FTLD and provides a new paradigm to further interrogate TDP-43 proteinopathies.
Collapse
Affiliation(s)
- Julie C Necarsulmer
- Department of Cell Biology and Physiology, University of North CarolinaChapel HillUnited States
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Jeremy M Simon
- UNC Neuroscience Center, University of North CarolinaChapel HillUnited States
- Carolina Institute for Developmental Disabilities, University of North CarolinaChapel HillUnited States
- Department of Genetics, University of North CarolinaChapel HillUnited States
| | - Baggio A Evangelista
- Department of Cell Biology and Physiology, University of North CarolinaChapel HillUnited States
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Youjun Chen
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Xu Tian
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Sara Nafees
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Ariana B Marquez
- Human Pluripotent Stem Cell Core, University of North CarolinaChapel HillUnited States
| | - Huijun Jiang
- Department of Biostatistics, University of North CarolinaChapel HillUnited States
| | - Ping Wang
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Deepa Ajit
- Department of Neurology, University of North CarolinaChapel HillUnited States
| | - Viktoriya D Nikolova
- Carolina Institute for Developmental Disabilities, University of North CarolinaChapel HillUnited States
- Department of Psychiatry, The University of North CarolinaChapel HillUnited States
| | - Kathryn M Harper
- Carolina Institute for Developmental Disabilities, University of North CarolinaChapel HillUnited States
- Department of Psychiatry, The University of North CarolinaChapel HillUnited States
| | - J Ashley Ezzell
- Department of Cell Biology & Physiology, Histology Research Core Facility, University of North CarolinaChapel HillUnited States
| | - Feng-Chang Lin
- Department of Biostatistics, University of North CarolinaChapel HillUnited States
| | - Adriana S Beltran
- Department of Genetics, University of North CarolinaChapel HillUnited States
- Human Pluripotent Stem Cell Core, University of North CarolinaChapel HillUnited States
- Department of Pharmacology, University of North CarolinaChapel HillUnited States
| | - Sheryl S Moy
- Carolina Institute for Developmental Disabilities, University of North CarolinaChapel HillUnited States
- Department of Psychiatry, The University of North CarolinaChapel HillUnited States
| | - Todd J Cohen
- Department of Cell Biology and Physiology, University of North CarolinaChapel HillUnited States
- Department of Neurology, University of North CarolinaChapel HillUnited States
- UNC Neuroscience Center, University of North CarolinaChapel HillUnited States
- Department of Biochemistry and Biophysics, University of North CarolinaChapel HillUnited States
| |
Collapse
|
13
|
Delfing BM, Laracuente XE, Olson A, Foreman KW, Paige M, Kehn-Hall K, Lockhart C, Klimov DK. Binding of viral nuclear localization signal peptides to importin-α nuclear transport protein. Biophys J 2023; 122:3476-3488. [PMID: 37542371 PMCID: PMC10502480 DOI: 10.1016/j.bpj.2023.07.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/23/2023] [Accepted: 07/27/2023] [Indexed: 08/06/2023] Open
Abstract
Using all-atom replica-exchange molecular dynamics simulations, we mapped the mechanisms of binding of the nuclear localization signal (NLS) sequence from Venezuelan equine encephalitis virus (VEEV) capsid protein to importin-α (impα) transport protein. Our objective was to identify the VEEV NLS sequence fragment that confers native, experimentally resolved binding to impα as well as to study associated binding energetics and conformational ensembles. The two selected VEEV NLS peptide fragments, KKPK and KKPKKE, show strikingly different binding mechanisms. The minNLS peptide KKPK binds non-natively and nonspecifically by adopting five diverse conformational clusters with low similarity to the x-ray structure 3VE6 of NLS-impα complex. Despite the prevalence of non-native interactions, the minNLS peptide still largely binds to the impα major NLS binding site. In contrast, the coreNLS peptide KKPKKE binds specifically and natively, adopting a largely homogeneous binding ensemble with a dominant, highly native-like conformational cluster. The coreNLS peptide retains most of native binding interactions, including π-cation contacts and a tryptophan cage. While KKPK binding is governed by a complex multistate free energy landscape featuring transitions between multiple binding poses, the coreNLS peptide free energy map is simple, exhibiting a single dominant native-like bound basin. We argue that the origin of the coreNLS peptide binding specificity is several electrostatic interactions formed by the two C-terminal amino acids, Lys10 and Glu11, with impα. The coreNLS sequence is then sufficient for native binding, but none of the amino acids flanking minNLS, including Lys10 and Glu11, are strictly necessary for the native pose. Our analyses indicate that the VEEV coreNLS sequence is virtually unique among human and viral proteins interacting with impα making it a potential target for VEEV-specific inhibitors.
Collapse
Affiliation(s)
- Bryan M Delfing
- School of Systems Biology, George Mason University, Manassas, Virginia
| | | | - Audrey Olson
- School of Systems Biology, George Mason University, Manassas, Virginia
| | - Kenneth W Foreman
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia
| | - Mikell Paige
- Department of Chemistry and Biochemistry, George Mason University, Manassas, Virginia
| | - Kylene Kehn-Hall
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | | | - Dmitri K Klimov
- School of Systems Biology, George Mason University, Manassas, Virginia.
| |
Collapse
|
14
|
McGoldrick P, Robertson J. Unraveling the impact of disrupted nucleocytoplasmic transport systems in C9orf72-associated ALS. Front Cell Neurosci 2023; 17:1247297. [PMID: 37720544 PMCID: PMC10501458 DOI: 10.3389/fncel.2023.1247297] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 08/08/2023] [Indexed: 09/19/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two adult-onset neurodegenerative diseases that are part of a common disease spectrum due to clinical, genetic, and pathological overlap. A prominent genetic factor contributing to both diseases is a hexanucleotide repeat expansion in a non-coding region of the C9orf72 gene. This mutation in C9orf72 leads to nuclear depletion and cytoplasmic aggregation of Tar DNA-RNA binding protein 43 (TDP-43). TDP-43 pathology is characteristic of the majority of ALS cases, irrespective of disease causation, and is present in ~50% of FTD cases. Defects in nucleocytoplasmic transport involving the nuclear pore complex, the Ran-GTPase cycle, and nuclear transport factors have been linked with the mislocalization of TDP-43. Here, we will explore and discuss the implications of these system abnormalities of nucleocytoplasmic transport in C9orf72-ALS/FTD, as well as in other forms of familial and sporadic ALS.
Collapse
Affiliation(s)
- Philip McGoldrick
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
15
|
Abstract
Biomolecular condensates are reversible compartments that form through a process called phase separation. Post-translational modifications like ADP-ribosylation can nucleate the formation of these condensates by accelerating the self-association of proteins. Poly(ADP-ribose) (PAR) chains are remarkably transient modifications with turnover rates on the order of minutes, yet they can be required for the formation of granules in response to oxidative stress, DNA damage, and other stimuli. Moreover, accumulation of PAR is linked with adverse phase transitions in neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In this review, we provide a primer on how PAR is synthesized and regulated, the diverse structures and chemistries of ADP-ribosylation modifications, and protein-PAR interactions. We review substantial progress in recent efforts to determine the molecular mechanism of PAR-mediated phase separation, and we further delineate how inhibitors of PAR polymerases may be effective treatments for neurodegenerative pathologies. Finally, we highlight the need for rigorous biochemical interrogation of ADP-ribosylation in vivo and in vitro to clarify the exact pathway from PARylation to condensate formation.
Collapse
Affiliation(s)
- Kevin Rhine
- Program in Cell, Molecular, Developmental Biology, and Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Hana M Odeh
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
| | - James Shorter
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
| | - Sua Myong
- Program in Cell, Molecular, Developmental Biology, and Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Physics Frontier Center (Center for the Physics of Living Cells), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| |
Collapse
|
16
|
Nie X, Xu Q, Xu C, Chen F, Wang Q, Qin D, Wang R, Gao Z, Lu X, Yang X, Wu Y, Gu C, Xie W, Li L. Maternal TDP-43 interacts with RNA Pol II and regulates zygotic genome activation. Nat Commun 2023; 14:4275. [PMID: 37460529 DOI: 10.1038/s41467-023-39924-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/30/2023] [Indexed: 07/20/2023] Open
Abstract
Zygotic genome activation (ZGA) is essential for early embryonic development. However, the regulation of ZGA remains elusive in mammals. Here we report that a maternal factor TDP-43, a nuclear transactive response DNA-binding protein, regulates ZGA through RNA Pol II and is essential for mouse early embryogenesis. Maternal TDP-43 translocates from the cytoplasm into the nucleus at the early two-cell stage when minor to major ZGA transition occurs. Genetic deletion of maternal TDP-43 results in mouse early embryos arrested at the two-cell stage. TDP-43 co-occupies with RNA Pol II as large foci in the nucleus and also at the promoters of ZGA genes at the late two-cell stage. Biochemical evidence indicates that TDP-43 binds Polr2a and Cyclin T1. Depletion of maternal TDP-43 caused the loss of Pol II foci and reduced Pol II binding on chromatin at major ZGA genes, accompanied by defective ZGA. Collectively, our results suggest that maternal TDP-43 is critical for mouse early embryonic development, in part through facilitating the correct RNA Pol II configuration and zygotic genome activation.
Collapse
Affiliation(s)
- Xiaoqing Nie
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qianhua Xu
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Chengpeng Xu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fengling Chen
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Qizhi Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Dandan Qin
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Rui Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zheng Gao
- Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xukun Lu
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Xinai Yang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yu Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chen Gu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Xie
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China.
- Tsinghua-Peking Center for Life Sciences, Beijing, China.
| | - Lei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
17
|
Ionescu A, Altman T, Perlson E. Looking for answers far away from the soma-the (un)known axonal functions of TDP-43, and their contribution to early NMJ disruption in ALS. Mol Neurodegener 2023; 18:35. [PMID: 37259156 DOI: 10.1186/s13024-023-00623-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 05/01/2023] [Indexed: 06/02/2023] Open
Abstract
Axon degeneration and Neuromuscular Junction (NMJ) disruption are key pathologies in the fatal neurodegenerative disease Amyotrophic Lateral Sclerosis (ALS). Despite accumulating evidence that axons and NMJs are impacted at a very early stage of the disease, current knowledge about the mechanisms leading to their degeneration remains elusive. Cytoplasmic mislocalization and accumulation of the protein TDP-43 are considered key pathological hallmarks of ALS, as they occur in ~ 97% of ALS patients, both sporadic and familial. Recent studies have identified pathological accumulation of TDP-43 in intramuscular nerves of muscle biopsies collected from pre-diagnosed, early symptomatic ALS patients. These findings suggest a gain of function for TDP-43 in axons, which might facilitate early NMJ disruption. In this review, we dissect the process leading to axonal TDP-43 accumulation and phosphorylation, discuss the known and hypothesized roles TDP-43 plays in healthy axons, and review possible mechanisms that connect TDP-43 pathology to the axon and NMJ degeneration in ALS.
Collapse
Affiliation(s)
- Ariel Ionescu
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Topaz Altman
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Eran Perlson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel.
- Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv, Israel.
| |
Collapse
|
18
|
He S, Valkov E, Cheloufi S, Murn J. The nexus between RNA-binding proteins and their effectors. Nat Rev Genet 2023; 24:276-294. [PMID: 36418462 DOI: 10.1038/s41576-022-00550-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2022] [Indexed: 11/25/2022]
Abstract
RNA-binding proteins (RBPs) regulate essentially every event in the lifetime of an RNA molecule, from its production to its destruction. Whereas much has been learned about RNA sequence specificity and general functions of individual RBPs, the ways in which numerous RBPs instruct a much smaller number of effector molecules, that is, the core engines of RNA processing, as to where, when and how to act remain largely speculative. Here, we survey the known modes of communication between RBPs and their effectors with a particular focus on converging RBP-effector interactions and their roles in reducing the complexity of RNA networks. We discern the emerging unifying principles and discuss their utility in our understanding of RBP function, regulation of biological processes and contribution to human disease.
Collapse
Affiliation(s)
- Shiyang He
- Department of Biochemistry, University of California, Riverside, CA, USA
- Center for RNA Biology and Medicine, Riverside, CA, USA
| | - Eugene Valkov
- RNA Biology Laboratory & Center for Structural Biology, Center for Cancer Research, National Cancer Institute (NCI), Frederick, MD, USA
| | - Sihem Cheloufi
- Department of Biochemistry, University of California, Riverside, CA, USA.
- Center for RNA Biology and Medicine, Riverside, CA, USA.
- Stem Cell Center, University of California, Riverside, CA, USA.
| | - Jernej Murn
- Department of Biochemistry, University of California, Riverside, CA, USA.
- Center for RNA Biology and Medicine, Riverside, CA, USA.
| |
Collapse
|
19
|
Sugeno N, Hasegawa T. Unraveling the Complex Interplay between Alpha-Synuclein and Epigenetic Modification. Int J Mol Sci 2023; 24:ijms24076645. [PMID: 37047616 PMCID: PMC10094812 DOI: 10.3390/ijms24076645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/21/2023] [Accepted: 03/31/2023] [Indexed: 04/05/2023] Open
Abstract
Alpha-synuclein (αS) is a small, presynaptic neuronal protein encoded by the SNCA gene. Point mutations and gene multiplication of SNCA cause rare familial forms of Parkinson’s disease (PD). Misfolded αS is cytotoxic and is a component of Lewy bodies, which are a pathological hallmark of PD. Because SNCA multiplication is sufficient to cause full-blown PD, gene dosage likely has a strong impact on pathogenesis. In sporadic PD, increased SNCA expression resulting from a minor genetic background and various environmental factors may contribute to pathogenesis in a complementary manner. With respect to genetic background, several risk loci neighboring the SNCA gene have been identified, and epigenetic alterations, such as CpG methylation and regulatory histone marks, are considered important factors. These alterations synergistically upregulate αS expression and some post-translational modifications of αS facilitate its translocation to the nucleus. Nuclear αS interacts with DNA, histones, and their modifiers to alter epigenetic status; thereby, influencing the stability of neuronal function. Epigenetic changes do not affect the gene itself but can provide an appropriate transcriptional response for neuronal survival through DNA methylation or histone modifications. As a new approach, publicly available RNA sequencing datasets from human midbrain-like organoids may be used to compare transcriptional responses through epigenetic alterations. This informatic approach combined with the vast amount of transcriptomics data will lead to the discovery of novel pathways for the development of disease-modifying therapies for PD.
Collapse
Affiliation(s)
- Naoto Sugeno
- Division of Neurology, Department of Neuroscience & Sensory Organs, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Takafumi Hasegawa
- Division of Neurology, Department of Neuroscience & Sensory Organs, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| |
Collapse
|
20
|
Herrera MG, Amundarain MJ, Santos J. Biophysical evaluation of the oligomerization and conformational properties of the N-terminal domain of TDP-43. Arch Biochem Biophys 2023; 737:109533. [PMID: 36740035 DOI: 10.1016/j.abb.2023.109533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 01/08/2023] [Accepted: 01/23/2023] [Indexed: 02/05/2023]
Abstract
TDP-43 is an RNA-binding protein that presents four domains comprising an N-terminal region, two RNA recognition motifs and a C-terminal region. The N-terminal domain (NTD) has a relevant role in the oligomerization and splicing activity of TDP-43. In this work, we have expressed, purified and biophysically characterized the region that includes residues 1 to 102 that contains the nuclear localization signal (residues 80-102, NLS). Furthermore, we have evaluated the oligomerization equilibrium for this protein fragment. Also, we have determined changes in the tertiary structure and its stability in a broad range of pH values by means of different spectroscopic methods. Additionally, we compared this fragment with the one that lacks the NLS employing experimental and computational methods. Finally, we evaluated the motion of dimeric forms to get insights into the conformational flexibility of this TDP-43 module in an oligomeric state. Our results suggest that this domain has a conformational plasticity in the vicinity of the single tryptophan of this domain (Trp68), which is enhanced by the presence of the nuclear localization signal. All these results help to understand the molecular features of the NTD of TDP-43.
Collapse
Affiliation(s)
- Maria Georgina Herrera
- Faculty of Exact and Natural Sciences, Institute of Biosciences, Biotechnology and Translational Biology (iB3), University of Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Institute of Biochemistry and Pathobiochemistry, Ruhr-Universität Bochum, Gebäude MA 2/143, Universitätsstraße 150, 44801, Bochum, Germany.
| | - Maria Julia Amundarain
- Faculty of Chemistry, OCIII, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Javier Santos
- Faculty of Exact and Natural Sciences, Institute of Biosciences, Biotechnology and Translational Biology (iB3), University of Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| |
Collapse
|
21
|
Khalil B, Chhangani D, Wren MC, Smith CL, Lee JH, Li X, Puttinger C, Tsai CW, Fortin G, Morderer D, Gao J, Liu F, Lim CK, Chen J, Chou CC, Croft CL, Gleixner AM, Donnelly CJ, Golde TE, Petrucelli L, Oskarsson B, Dickson DW, Zhang K, Shorter J, Yoshimura SH, Barmada SJ, Rincon-Limas DE, Rossoll W. Nuclear import receptors are recruited by FG-nucleoporins to rescue hallmarks of TDP-43 proteinopathy. Mol Neurodegener 2022; 17:80. [PMID: 36482422 PMCID: PMC9733332 DOI: 10.1186/s13024-022-00585-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/23/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Cytoplasmic mislocalization and aggregation of TAR DNA-binding protein-43 (TDP-43) is a hallmark of the amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) disease spectrum, causing both nuclear loss-of-function and cytoplasmic toxic gain-of-function phenotypes. While TDP-43 proteinopathy has been associated with defects in nucleocytoplasmic transport, this process is still poorly understood. Here we study the role of karyopherin-β1 (KPNB1) and other nuclear import receptors in regulating TDP-43 pathology. METHODS We used immunostaining, immunoprecipitation, biochemical and toxicity assays in cell lines, primary neuron and organotypic mouse brain slice cultures, to determine the impact of KPNB1 on the solubility, localization, and toxicity of pathological TDP-43 constructs. Postmortem patient brain and spinal cord tissue was stained to assess KPNB1 colocalization with TDP-43 inclusions. Turbidity assays were employed to study the dissolution and prevention of aggregation of recombinant TDP-43 fibrils in vitro. Fly models of TDP-43 proteinopathy were used to determine the effect of KPNB1 on their neurodegenerative phenotype in vivo. RESULTS We discovered that several members of the nuclear import receptor protein family can reduce the formation of pathological TDP-43 aggregates. Using KPNB1 as a model, we found that its activity depends on the prion-like C-terminal region of TDP-43, which mediates the co-aggregation with phenylalanine and glycine-rich nucleoporins (FG-Nups) such as Nup62. KPNB1 is recruited into these co-aggregates where it acts as a molecular chaperone that reverses aberrant phase transition of Nup62 and TDP-43. These findings are supported by the discovery that Nup62 and KPNB1 are also sequestered into pathological TDP-43 aggregates in ALS/FTD postmortem CNS tissue, and by the identification of the fly ortholog of KPNB1 as a strong protective modifier in Drosophila models of TDP-43 proteinopathy. Our results show that KPNB1 can rescue all hallmarks of TDP-43 pathology, by restoring its solubility and nuclear localization, and reducing neurodegeneration in cellular and animal models of ALS/FTD. CONCLUSION Our findings suggest a novel NLS-independent mechanism where, analogous to its canonical role in dissolving the diffusion barrier formed by FG-Nups in the nuclear pore, KPNB1 is recruited into TDP-43/FG-Nup co-aggregates present in TDP-43 proteinopathies and therapeutically reverses their deleterious phase transition and mislocalization, mitigating neurodegeneration.
Collapse
Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Deepak Chhangani
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
| | - Melissa C Wren
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, USA
| | - Jannifer H Lee
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, USA
| | - Xingli Li
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | | | - Chih-Wei Tsai
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Gael Fortin
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Dmytro Morderer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Feilin Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Chun Kim Lim
- Graduate School of Biostudies, Kyoto University, Yoshida-konoe, Sakyo-ku, Kyoto, Japan
| | - Jingjiao Chen
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Geriatric Department, Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Ching-Chieh Chou
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Cara L Croft
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
- UK Dementia Research Institute at University College London, London, UK
| | - Amanda M Gleixner
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, 15261, USA
| | - Christopher J Donnelly
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, 15261, USA
| | - Todd E Golde
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
| | | | | | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Shige H Yoshimura
- Graduate School of Biostudies, Kyoto University, Yoshida-konoe, Sakyo-ku, Kyoto, Japan
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Diego E Rincon-Limas
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, 32610, USA
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL, 32610, USA
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
| |
Collapse
|
22
|
Doll SG, Cingolani G. Importin α/β and the tug of war to keep TDP-43 in solution: quo vadis? Bioessays 2022; 44:e2200181. [PMID: 36253101 PMCID: PMC9969346 DOI: 10.1002/bies.202200181] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 09/29/2022] [Accepted: 10/05/2022] [Indexed: 11/10/2022]
Abstract
The transactivation response-DNA binding protein of 43 kDa (TDP-43) is an aggregation-prone nucleic acid-binding protein linked to the etiology of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Lobar Degeneration (FTLD). These conditions feature the accumulation of insoluble TDP-43 aggregates in the neuronal cytoplasm that lead to cell death. The dynamics between cytoplasmic and nuclear TDP-43 are altered in the disease state where TDP-43 mislocalizes to the cytoplasm, disrupting Nuclear Pore Complexes (NPCs), and ultimately forming large fibrils stabilized by the C-terminal prion-like domain. Here, we review three emerging and poorly understood aspects of TDP-43 biology linked to its aggregation. First, how post-translational modifications in the proximity of TDP-43 N-terminal domain (NTD) promote aggregation. Second, how TDP-43 engages FG-nucleoporins in the NPC, disrupting the pore permeability and function. Third, how the importin α/β heterodimer prevents TDP-43 aggregation, serving both as a nuclear import transporter and a cytoplasmic chaperone.
Collapse
Affiliation(s)
- Steven G. Doll
- Dept. of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Gino Cingolani
- Dept. of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA,Corresponding author: Gino Cingolani,
| |
Collapse
|
23
|
Li TD, Murano K, Kitano T, Guo Y, Negishi L, Siomi H. TDP-43 safeguards the embryo genome from L1 retrotransposition. SCIENCE ADVANCES 2022; 8:eabq3806. [PMID: 36417507 PMCID: PMC9683724 DOI: 10.1126/sciadv.abq3806] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Transposable elements (TEs) are genomic parasites that propagate within the host genome and introduce mutations. Long interspersed nuclear element-1 (LINE-1 or L1) is the major TE class, which occupies nearly 20% of the mouse genome. L1 is highly active in mammalian preimplantation embryos, posing a major threat to genome integrity, but the mechanism of stage-specific protection against L1 retrotransposition is unknown. Here, we show that TAR DNA-binding protein 43 (TDP-43), mutations in which constitute a major risk factor for amyotrophic lateral sclerosis, inhibits L1 retrotransposition in mouse embryonic stem cells (mESCs) and preimplantation embryos. Knockdown of TDP-43 resulted in massive genomic L1 expansion and impaired cell growth in preimplantation embryos and ESCs. Functional analysis demonstrated that TDP-43 interacts with L1 open reading frame 1 protein (L1 ORF1p) to mediate genomic protection, and loss of this interaction led to derepression of L1 retrotransposition. Our results identify TDP-43 as a guardian of the embryonic genome.
Collapse
Affiliation(s)
- Ten D. Li
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Kensaku Murano
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Tomohiro Kitano
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Youjia Guo
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Lumi Negishi
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo 113-0032, Japan
| | - Haruhiko Siomi
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| |
Collapse
|
24
|
Damizia M, Altieri L, Lavia P. Non-transport roles of nuclear import receptors: In need of the right balance. Front Cell Dev Biol 2022; 10:1041938. [PMID: 36438555 PMCID: PMC9686011 DOI: 10.3389/fcell.2022.1041938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 10/21/2022] [Indexed: 11/12/2023] Open
Abstract
Nuclear import receptors ensure the recognition and transport of proteins across the nuclear envelope into the nucleus. In addition, as diverse processes as mitosis, post-translational modifications at mitotic exit, ciliogenesis, and phase separation, all share a common need for regulation by nuclear import receptors - particularly importin beta-1 and importin beta-2/transportin - independent on nuclear import. In particular, 1) nuclear import receptors regulate the mitotic spindle after nuclear envelope breakdown, 2) they shield cargoes from unscheduled ubiquitination, regulating their timely proteolysis; 3) they regulate ciliary factors, crucial to cell communications and tissue architecture during development; and 4) they prevent phase separation of toxic proteins aggregates in neurons. The balance of nuclear import receptors to cargoes is critical in all these processes, albeit in opposite directions: overexpression of import receptors, as often found in cancer, inhibits cargoes and impairs downstream processes, motivating the therapeutic design of specific inhibitors. On the contrary, elevated expression is beneficial in neuronal contexts, where nuclear import receptors are regarded as potential therapeutic tools in counteracting the formation of aggregates that may cause neurodegeneration. This paradox demonstrates the amplitude of nuclear import receptors-dependent functions in different contexts and adds complexity in considering their therapeutic implications.
Collapse
Affiliation(s)
- Michela Damizia
- Department of Cellular, Computational and Integrated Biology (CIBIO), University of Trento, Trento, Italy
| | - Ludovica Altieri
- Institute of Molecular Biology and Pathology (IBPM), CNR National Research Council of Italy, Sapienza University of Rome, Rome, Italy
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| | - Patrizia Lavia
- Institute of Molecular Biology and Pathology (IBPM), CNR National Research Council of Italy, Sapienza University of Rome, Rome, Italy
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| |
Collapse
|